Tornadoes · United States · Michigan · 2010
EF1 tornado, Saint Clair County, Michigan, June 27, 2010
This EF1 tornado ran 2.9 miles across Saint Clair County on June 27, 2010, touching down at 7:06 PM EDT and reaching 250 yards wide. It killed 1 person and injured 4, and did $700,000 of property damage.
The rating scale
Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
EF2111 to 135 mph
Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.
EF3136 to 165 mph
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
EF5over 200 mph
Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.
Unrated
The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.
The record
- Rating
- EF1
- Date
- June 27, 2010
- Touchdown
- 7:06 PM EDT (23:06 UTC)
- Lifted
- 7:10 PM EDT (23:10 UTC)
- On the ground
- 4 minutes
- Path length
- 2.9 miles (4.7 km)
- Path width
- 250 yards (229 m)
- Deaths
- 1
- Injuries
- 4
- Property damage
- $700,000
- County
- Saint Clair County
- Touchdown point
- 42.994, -82.612
- Lift-off point
- 42.995, -82.554
- Record number
- 1006271706-01
The warnings
No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.
Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.
The forecast that day
The Storm Prediction Center had this point in a Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:44 UTC.
SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.
The air that afternoon
The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.
Detroit, MI (KDTX), 12:00Z
11.1 hours before the tornado, 75 km from the path. June 27, 2010.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -77698 J/kg
- Surface CAPE
- 11 J/kg
- Mixed-layer LCL
- 948 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 24 m²/s²
- 0-3 km storm-relative helicity
- 13 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
- 0-3 km lapse rate
- 3.9 K/km
Detroit, MI (KDTX), 00:00Z
0.9 hours after it, 75 km from the path. June 28, 2010.
- Mixed-layer CAPE
- 1357 J/kg
- Mixed-layer CIN
- -2 J/kg
- Surface CAPE
- 1668 J/kg
- Mixed-layer LCL
- 682 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 95 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 2.3
- 0-3 km lapse rate
- 6.3 K/km
The radar
The Detroit radar (KDTX), 79 km away, was scanning. The volume nearest the touchdown began at 23:07 UTC.
Open the radar archive at this moment, over the track
Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 21:06 UTC | TSTM WND DMG | S Marlette | Sanilac, MI | TREE DOWN ON HOUSE AND POWER LINES DOWN. |
| 23:06 UTC | TORNADO | 2 W Wadhams | St. Clair, MI | *** 1 FATAL, 4 INJ *** A NWS SURVEY TEAM CONFIRMED THAT A TORNADO TOUCHED DOWN NEAR THE INTERSECTION OF LAPEER AND RABIDUE ROADS AT APPROXIMATELY 706 PM EDT. THE TORNADO CONTINUED EASTWARD BEFORE LIFTING AT 710 PM EDT NE |
| 23:07 UTC | TSTM WND DMG | 2 W Wadhams | St. Clair, MI | *** 1 FATAL, 4 INJ *** WIND DAMAGE TO FORT TRODD CAMPGROUND. SEVERAL CAMPERS OVERTURNED AND THROWN INTO POND. |
| 23:07 UTC | TORNADO | 2 W Wadhams | St. Clair, MI | NWS SURVEY CONFIRMED A TORNADO TOUCHDOWN IN CLYDE TOWNSHIP. THE TORNADO WAS RATED AN EF1 WITH A MAXIMUM PATH WIDTH OF 250 YDS. |
| 23:20 UTC | TSTM WND DMG | 2 W Wadhams | St. Clair, MI | *** 2 FATAL *** WIND DAMAGE TO FORT TRODD CAMPGROUND. SEVERAL TRAILERS OVERTURNED AND THROWN INTO POND. |
| 00:32 UTC | TORNADO | 1 Se Marlette | Sanilac, MI | A NWS SURVEY TEAM CONFIRMED THAT A TORNADO TOUCHED DOWN ON EUCLID STREET JUST EAST OF STERLING STREET AT APPROXIMATELY 832 PM EDT. THE TORNADO CONTINUED EASTWARD BEFORE LIFTING AT 834 PM EDT JUST WEST OF BUTLER ROAD. EF0 |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2010 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are
The other tornadoes of June 27, 2010
8 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| June 27 | 1:08 PM EDT | EF0 | Van Buren, MI | 0.7 | 50 | $100,000 | ||
| June 27 | 1:20 PM CDT | EF1 | Racine, WI | 4.6 | 100 | 1 | $75,000 | |
| June 27 | 2:31 PM EDT | EF1 | Wayne, MI | 1.4 | 200 | $500,000 | ||
| June 27 | 6:54 PM EDT | EF1 | Ashtabula, OH | 2.3 | 100 | $300,000 | ||
| June 27 | 7:36 PM EDT | EF0 | Erie, PA | 0.2 | 75 | $120,000 | ||
| June 27 | 8:32 PM EDT | EF0 | Sanilac, MI | 0.5 | 50 | $75,000 | ||
| June 27 | 9:05 PM CDT | EF0 | Jefferson, IL | 0.3 | 50 | $2,000 | ||
| June 27 | 11:05 PM EDT | EF1 | Allegany, NY | 7.4 | 250 | $75,000 |
What this means
Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.